Place A Rack In The Center Of The Oven.
Do Not Preheat The Oven.
Grease The Bottom And Sides Of A 10″ Tube Pan Lightly With Vegetable Shortening.
Dust With Flour, Shake Out The Excess Flour, And Set The Pan Aside.
Place The Flour In A Medium-Size Bowl And Stir In The Salt.
Set Aside.
Separate The Eggs, Placing The Yolks In A Medium-Size Mixing Bowl And The Whites In A Large Mixing Bowl.
Set The Whites Aside.
Whisk The Milk And Vanilla Into The Yolks Until They Are Well Blended, And Set The Mixture Aside.
Beat The Egg Whites With An Electric Mixer On High Speed Until Soft Peaks Form, About 2 Minutes.
Set Them Aside.
Place The Butter, Shortening, And Sugar In Another Large Mixing Bowl, And With The Same Beaters, Beat On Medium-High Speed Until The Mixture Is Well Creamed And Lightened In Color, Beating For 2 Minutes And Scraping Down The Sides Of The Bowl Once Or Twice.
Reduce The Mixer Speed To Low And Blend In A Third Of The Flour Mixture Until Combined.
Add Half Of The Milk Mixture Until Combined.
Add Another Third Of The Flour, Then The Second Half Of The Milk, Then The Last Of The Flour.
The Batter Will Be Thick.
Remove The Beaters, And Pour The Beaten Egg Whites On Top Of The Cake Batter.
Fold The Whites Into The Batter With A Rubber Spatula, Using An Over-And-Under Folding Method, Just Incorporating The Whites.
Turn The Batter Into The Prepared Pan, And Smooth The Top.
Place The Pan On The Center Rack Of The Cold Oven.
Shut The Door.
Now Heat The Oven To 300°F.
Bake The Cake For 45 Minutes.
Increase The Oven Temperature To 325°F.
Bake Until The Cake Is Golden Brown And A Toothpick Inserted In The Center Comes Out Clean, About 30 Minutes.
Remove The Cake From The Oven, And Let The Cake Cool In The Pan On A Wire Rack For 20 Minutes.
It Will Fall About An Inch As It Cools.
Run A Knife Around The Edges, And Invert The Cake Once And Then Again So It Rests Right Side Up On The Rack.
Let The Cake Cool For 1 Hour Before Slicing.
The Crust Will Be Delicate And Crispy.
This Cake Stores Well Up To A Week At Room Temperature And Can Be Frozen For Up To 6 Months.
